/Engine/Source/Runtime/Engine/Classes/Particles/SubUV/ParticleModuleSubUVMovie.h
Determine the current image index to use...
float The image index with interpolation amount as the fractional portion.
virtual float DetermineImageIndex ( [FParticleEmitterInstance](API\Runtime\Engine\FParticleEmitterInstance) * Owner, int32 Offset, [FBaseParticle](API\Runtime\Engine\FBaseParticle) * Particle, EParticleSubUVInterpMethod InterpMethod, [FFullSubUVPayload](API\Runtime\Engine\FFullSubUVPayload) & SubUVPayload, float DeltaTime )